A stock symbol or ticker symbol is a short abbreviation used to uniquely identify publicly traded shares of a particular stock on a particular stock market. A stock symbol may consist of letters, numbers or a combination of both. «Ticker symbol» refers to the symbols that were printed on the ticker tape of a ticker tape machine. U.S stock symbol history In the United States, modern letter-only ticker symbols were developed by Standard & Poor’s (S&P) to bring a national standard to investing. Previously, a single company could have many different ticker symbols as they varied between the dozens of individual stock markets. The term ticker refers to the noise made by the ticker tape machines once widely used by stock exchanges. The S&P system was later standardized by the securities industry and modified as years passed. Stock symbols for preferred stock have not been standardized.